The proposed study will examine the cultural equivalence of the Autism Diagnostic Interview Revised (ADI-R) for a US Latino population. We propose 3 aims: (1) to assess the reliability of the ADI-R Spanish version among Spanish speaking parents of children with autism and intellectual disabilities;(2) To investigate the validity of the ADI-R in a sample of Latino parents of children with autism and intellectual disabilities;and (3) To investigate the meaning and perceived severity of symptoms in relation to the norms of the participant's family and culture. The proposed study builds on an existing study of Latino children on the autism spectrum and their families and will recruit 25 additional children who have intellectual disabilities. The study will utilize the expertise of bicultural and bilingual researchers that have extensive training experience with the ADI-R and cross cultural research. This study will establish a body of knowledge about the reliability and validity of a commonly utilized diagnostic measure with Latino populations which will reduce barriers for Latino children with ASD to receive important intervention services. PUBLIC HEALTH RELEVANCE: The proposed study will provide a body of data from which significant future research on Latinos with an autism spectrum disorder may be built by examining the cultural equivalence of one of the most widely accepted autism diagnostic instruments. Such data are particularly relevant as Latinos are the fastest growing minority group in the U.S. and have been underrepresented in autism diagnosis and services.